Inhalation of environmental stressors & chronic inflammation: autoimmunity and neurodegeneration

Human life expectancy and welfare has decreased because of the increase in environmental stressors in the air. An environmental stressor is a natural or human-made component present in our environment that upon reaching an organic system produces a coordinated response. This response usually involves a modification of the metabolism and physiology of the system. Inhaled environmental stressors damage the airways and lung parenchyma, producing irritation, recruitment of inflammatory cells, and oxidative modification of biomolecules. Oxidatively modified biomolecules, their degradation products, and adducts with other biomolecules can reach the systemic circulation, and when found in higher concentrations than normal they are considered to be biomarkers of systemic oxidative stress and inflammation. We classify them as metabolic stressors because they are not inert compounds; indeed, they amplify the inflammatory response by inducing inflammation in the lung and other organs. Thus the lung is not only the target for environmental stressors, but it is also the source of a number of metabolic stressors that can induce and worsen pre-existing chronic inflammation. Metabolic stressors produced in the lung have a number of effects in tissues other than the lung, such as the brain, and they can also abrogate the mechanisms of immunotolerance. In this review, we discuss recent published evidence that suggests that inflammation in the lung is an important connection between air pollution and chronic inflammatory diseases such as autoimmunity and neurodegeneration, and we highlight the critical role of metabolic stressors produced in the lung. The understanding of this relationship between inhaled environmental pollutants and systemic inflammation will help us to: (1) understand the molecular mechanism of environment-associated diseases, and (2) find new biomarkers that will help us prevent the exposure of susceptible individuals and/or design novel therapies.     

Synergistic effects of drought and ascorbic acid on growth,mineral nutrients and oxidative defense system in canola (Brassica napus L.) plants

A study was conducted to find out the role of ascorbic acid (AsA) in modulating growth and different physio-biochemical attributes of canola plants under well-watered as well as water-deficit conditions. Drought stress imposed on 60 % field capacity significantly decreased the shoot and root fresh and dry weights, leaf chlorophyll contents, shoot and root P, root K⁺, and activity of CAT enzyme, while increased chlorophyll a/b contents, MDA, NPQ, leaf total phenolics, free proline and GB contents in both canola cultivars. Foliar-applied varying levels (50, 100 and 150 mg L^?1) of AsA enhanced shoot and root fresh and root dry weights, qN, NPQ, shoot and root P, AsA as well as the activity of POD enzyme particularly under drought stress conditions. Of both canola cultivars, cv. Dunkeld was higher in shoot fresh weights, ETR and F _v /F _m, MDA, proline and GB contents, and POD activity, however, cv. Cyclone in total phenolics and qN under well-watered and water-deficit conditions. Overall, the foliar-applied AsA had a positive effect, though not marked, on salt sensitive cv. Cyclone in terms of improved growth and other attributes, whereas exogenously applied AsA had a non-significant effect on relatively salt tolerant cv. Dunkeld.     

Kinetic and thermodynamic study of cloned thermostable endo-1,4-β-xylanase from Thermotoga petrophila in mesophilic host

The 1,044 bp endo-1,4-β-xylanase gene of a hyperthermophilic Eubacterium, "Thermotoga petrophila RKU 1" (T. petrophila) was amplified, from the genomic DNA of donor bacterium, cloned and expressed in mesophilic host E. coli strain BL21 Codon plus. The extracellular target protein was purified by heat treatment followed by anion and cation exchange column chromatography. The purified enzyme appeared as a single band, corresponding to molecular mass of 40 kDa, upon SDS-PAGE. The pH and temperature profile showed that enzyme was maximally active at 6.0 and 95 °C, respectively against birchwood xylan as a substrate (2,600 U/mg). The enzyme also exhibited marked activity towards beech wood xylan (1,655 U/mg). However minor activity against CMC (61 U/mg) and β-Glucan barley (21 U/mg) was observed. No activity against Avicel, Starch, Laminarin and Whatman filter paper 42 was observed. The K(m), V(max) and K (cat) of the recombinant enzyme were found to be 3.5 mg ml(-1), 2778 μmol mg(-1)min(-1) and 2,137,346.15 s(-1), respectively against birchwood xylan as a substrate. The recombinant enzyme was found very stable and exhibited half life (t(?)) of 54.5 min even at temperature as high as 96 °C, with enthalpy of denaturation (ΔH*(D)), free energy of denaturation (ΔG*(D)) and entropy of denaturation (ΔS*(D)) of 513.23 kJ mol(-1), 104.42 kJ mol(-1) and 1.10 kJ mol(-1)K(-1), respectively at 96 °C. Further the enthalpy (ΔH*), Gibbs free energy (ΔG*) and entropy (ΔS*) for birchwood xylan hydrolysis by recombinant endo-1,4-β-xylanase were calculated at 95 °C as 62.45 kJ mol(-1), 46.18 kJ mol(-1) and 44.2 J mol(-1) K(-1), respectively.     

Interaction Between Nociceptin/Orphanin FQ and Adrenergic System on Food Intake in Neonatal Chicken

The information emerging from the studies demonstrates adrenergic system and nociceptin/orphanin FQ (N/OFQ) play a crucial role on appetite regulation but there is no information for their interaction. The purpose of this study was to examine the effects of intracerebroventricular (ICV) injection of prazosin (α₁ receptor antagonist), yohimbine (α₂ receptor antagonist), metoprolol (β₁ adrenergic receptor antagonist), ICI 118,551 (β₂ adrenergic receptor antagonist) and SR59230R (β₃ adrenergic receptor antagonist) on N/OFQ-induced hyperphagia by 3-h food-deprived neonatal broiler chicken. In experiment 1, chicken injected with saline, prazosin (10 nmol), N/OFQ (16 nmol) and co-injection of prazosin + N/OFQ. In experiment 2, ICV injection of saline, yohimbine (13 nmol), N/OFQ (16 nmol) and yohimbine + N/OFQ applied to the birds. In experiment 3, injections were saline, metoprolol (24 nmol), N/OFQ (16 nmol) and metoprolol + N/OFQ. In experiment 4, the birds received ICV injection of saline, ICI 118,551 (5 nmol), (C) N/OFQ (16 nmol) and co-administration of ICI 118,551 + N/OFQ. In experiment 5, chicken injected with saline, SR59230R (20 nmol), N/OFQ (16 nmol) and SR59230R + N/OFQ. Then, cumulative food intake was recorded until 120 min after injection. According to the results, ICV injection of N/OFQ significantly increased food intake (P < 0.001). The effect of N/OFQ significantly amplified by co-injection of N/OFQ + β₂ adrenergic receptor antagonist (P < 0.001). Also, administration of β₁ or β₃ adrenergic receptor antagonist had no effect on N/OFQ-induced hyperphagia (P > 0.05). These results suggest that the effect of N/OFQ on cumulative food intake is mediated via β₂ adrenergic receptors in neonatal chicken.     

Comparative study of effects of polyols, salts, and alcohols on trichloroacetic acid-induced state of cytochrome c

A systematic investigation of the effect of polyethylene glycols, salts, and alcohols on the trichloroacetic acid (TCA)-induced state of ferricytochrome c was made using various spectroscopic techniques. Native cytochrome c (Cyt c) has a fluorescence maximum at 335 nm, whereas the TCA-induced state of Cyt c has a red shift of 7 nm with enhanced fluorescence intensity. The near- and far-UV CD spectra showed a significant loss of tertiary and secondary structure, although the protein is relatively less unfolded as compared with a conformation at pH 2.0. Addition of 70% (v/v) polyols to TCA (3.3 mM)-induced state of Cyt c resulted in increased 1-anilino-8-naphthalene sulfonate binding and increased mean residue ellipticity at 222 nm, indicating increase in compactness with enhanced exposure of hydrophobic surface area. Also, the stabilizing effect of salts and alcohols on the TCA-induced state was studied and compared with their effect on trifluoroacetic acid-unfolded state of Cyt c. Among all the polyols, salts, and alcohols studied, PEG-400, K3[Fe(CN)6], and butanol were the most efficient in inducing secondary structure in TCA-induced state as examined by the above-mentioned spectroscopic techniques. For salts, the efficiency in inducing the secondary structure followed the order K3[Fe(CN)6] > KClO4 > K2SO4 > KCl. For alcohols, this order was found to be as follows: butanol > propanol > ethanol > methanol.     

Inter- and intraspecific diversity of ontogeny and fecundity patterns in relation to reproductive strategy choice in Myomorpha (Rodentia: Calomyscidae,Cricetidae, Muridae)

Studying the life history of various organisms is essential for ecological and evolutionary inferences. However, publications regarding models of evolutionary shifts to either r- or K-reproductive strategies are scarce. Here, the combined original and previously published data on reproduction and development of Goodwin’s brush-tailed mouse (Calomyscus elburzensis), golden hamster (Mesocricetus auratus), and house mouse (Mus musculus) were compared. An adult male and female in estrous state (from each species) were coupled with each other for a night and embryos were harvested at embryonic days (E) 10–17 from pregnant females. The mean gestation period in Goodwin’s brush-tailed mouse was 31.5?±?2.1 days; growth was rapid at the first half of this period and after that it was reduced by half. During the postnatal period, growth was rapid up to weaning, but after day 35, the rate of growth decreased abruptly. Growth rate of head and body length was very rapid prior to weaning (PN35) in comparison with weight but the rates of the two characters were inversed following weaning. Totally, weight gain was more dynamic in rate, as compared with head and body length, up to adultness. For golden hamster and house mouse, gestation period was 15.6?±?0.8 and 20.8?±?0.8 days, respectively. Growth was slow during approximately the first half of the gestation period in both species but increased during the second half. During postnatal period in golden hamster, growth rate of head and body length was rapid both before and after weaning as compared with that of weight. However, head and body length showed a stable rate of growth before and after weaning (around PN15), but for body weight, the growth rate was slightly faster after weaning. Similarly, changes in head and body length in house mouse were rapid both before and after weaning (PN16) as compared with that of weight. Since approximately two-fold increases were observed in the growth rates of weight and head and body length in the second stage of postnatal development (PN16-adult) compared with the rates during the first stage (PN0-PN16), both showed dynamic changes during the postnatal development in this species. Typically, r-strategic house mouse appeared to be more similar in early morphological development to comparatively K-strategic Goodwin’s brush-tailed mouse, than to comparatively r-strategic golden hamster. Nevertheless, growth rate and pattern were different in the three species after birth. Hence, results showed that peculiarities of association between an ontogenetic pattern and a tendency in reproductive strategy can differ in diverse groups of myomorph rodents.

     

Stevia rebaudiana Bertoni responses to salt stress and chitosan elicitor

This study examined the effect of chitosan elicitor with four different concentrations (0, 0.2, 0.4 and 0.6 g/l) on physiological and biochemical properties of stevia under four levels of salinity stress (0, 50, 100, 150 mM level of NaCl). Salt stress caused reduction of chlorophyll a (Chl a), chlorophyll b (Chl b), total chlorophyll, carotenoid and total protein content. The increment of malondialdehyde (MDA) content was not significant in all NaCl levels, while the CAT and POX activities were increased as well as stevioside and rebaudioside A under salinity stress. On one side, chitosan treatments could compensate the reduction of physiological traits such as photosynthetic pigments and protein content. On the other side, chitosan caused multiple increases in malondialdehyde content, antioxidant enzymes activity (catalase and peroxidase), steviol glycosides (stevioside and rebaudioside A) under salt stress. We report for the first time, the potential of chitosan to enhance salinity-tolerant abilities in stevia through increment of the salt-adaptive factors and to diminish harmful damages caused by NaCl stress.     

Host-ectoparasite associations; the role of host traits,season and habitat on parasitism interactions of the rodents of northeastern Iran

Rodents play a significant role as reservoirs of zoonotic diseases. Nevertheless, in general their ectoparasite assemblage and host-ectoparasite associations are poorly known. This study intended to provide new insights into the relationships between ectoparasites and rodents in northeastern Iran. Rodents were captured using live traps during the years 2016–2020, and their ectoparasites were collected. Parasitological indices such as infestation rate, prevalence and mean intensity of infestation were analyzed. A total of 284 rodents, belonging to 17 species, were trapped and found to be infested by 178 ectoparasites from five orders Siphonaptera, Phthiraptera, Ixodida, Mesostigmata and Trombidiformes. The overall infestation rate was 50.3%. The flea Nosopsyllus fasciatus and the louse Polyplax asiatica dominated among all fleas and lice, respectively. Haemaphysalis punctata and Haemolaelaps sp. were recorded as the most abundant tick and mite, respectively. Nosopsyllus fasciatus exhibited low and Polyplax asiatica moderate host specificity. Approximately 64.2% of ectoparasites shared more than one host, and others were singletons. Seasonal fluctuations were found in the occurrence of ectoparasite; fleas and lice were more abundant in spring and winter, respectively. Ticks demonstrated high abundance in spring and summer and mites were more common in autumn. The overall prevalence of ectoparasite on male rodents was greater than that on females (56.4% vs. 44.4%), while similar mean intensities were detected for both sexes. This study extends the knowledge on the distribution, seasonality and host choice of four main groups of ectoparasites in association with rodents. Further studies are needed to provide deep insight into how relationships and interactions between ectoparasite and rodents are formed, and how they can be applied in epidemiology.     

Intracellular Survival and Persistence of Chlamydia muridarum Is Determined by Macrophage Polarization

Macrophages can display a number of distinct phenotypes, known collectively as polarized macrophages. The best defined of these phenotypes are the classically-activated, interferon gamma (IFNγ)/LPS induced (M1) and alternatively-activated, IL-4 induced (M2) macrophages. The goal of this study is to characterize macrophage- Chlamydia interactions in the context of macrophage polarization. Here we use Chlamydia muridarum and murine bone-marrow derived macrophages to show Chlamydia does not induce M2 polarization in macrophages as a survival strategy. Unexpectedly, the infection of macrophages was silent with no upregulation of M1 macrophage-associated genes. We further demonstrate that macrophages polarized prior to infection have a differential capacity to control Chlamydia . M1 macrophages harbor up to 40-fold lower inclusion forming units (IFU) than non-polarized or M2 polarized macrophages. Gene expression analysis showed an increase in 16sRNA in M2 macrophages with no change in M1 macrophages. Suppressed Chlamydia growth in M1 macrophages correlated with the induction of a bacterial gene expression profile typical of persistence as evident by increased Euo expression and decreased Omp1 and Tal expression. Observations of permissive Chlamydia growth in non-polarized and M2 macrophages and persistence in M1 macrophages were supported through electron microscopy. This work supports the importance of IFNγ in the innate immune response to Chlamydia . However, demonstration that the M1 macrophages, despite an antimicrobial signature, fail to eliminate intracellular Chlamydia supports the notion that host–pathogen co-evolution has yielded a pathogen that can evade cellular defenses against this pathogen, and persist for prolonged periods of time in the host.